This is the base mix-in shared by all model elements that can be rendered into the
UI presentation of the application. Its main job is to manage the bindings between
the concrete element and the UI 'widget' representing it in the UI.

setRenderer

isToBeRendered

boolean isToBeRendered()

Returns the value of the 'To Be Rendered' attribute.
The default value is "true".

This field controls whether the given UIElement should be displayed within
the application. Note that due to lazy loading it is possible to have this field
set to true but to not have actually rendered the element itself (it does show up
as a tab on the appropiate stack but will only be rendered when that tab is
selected.

setOnTop

isVisible

Returns the value of the 'Visible' attribute.
The default value is "true".

This field determines whether or not the given UIElement appears in the presentation
or whether it should be 'cached' for specialized use. Under normal circumstances
this flag should always be 'true'.

The MinMaxAddon uses this flag for example when a stack becomes minimized. By
setting the flag to false the stack's widget is cleanly removed from the UI but
is still 'rendered'. Once the widget has been cached the minimized stack can then
display the widget using its own technques.

getParent

Returns the value of the 'Parent' container reference.
It is bidirectional and its opposite is 'Children'.

This field is a reference to this element's container. Note that while this field is valid
for most UIElements there are a few (such as TrimBars and the Windows associated
with top level windows and perspectives) where this will return 'null'

getContainerData

This is a persistend field that may be used by the parent element's renderer
to maintain any data that it needs to control the container. For example this is where
the SashRenderer stores the 'weight' of a particular element.

NOTE: This field is effectively deprecated in favor of the parent renderer
simply adding a new keyed value to the UIElement's 'persistentData' map.

getCurSharedRef

This is a transient (i.e. non-persisted) field which is used in conjunction with
MPlaceholders which are used to share elements actoss multiple perspectives. This
field will point back to the MPlaceholder (if any) currently hosting this one.

getAccessibilityPhrase

This field is provided as a way to inform accessibility screen readers with extra
information. The intent is that the reader should 'say' this phrase as well as what
it would normally emit given the widget hierarchy.